A good day!

Arizona some years ago went to a "modified open" primary. In it, members of the three parties with regular ballot access (Demo, Repub and Libertarian) have to vote in their own parties' primaries. Independents and members of parties without ballot access (Greens, etc.) however can vote in any major party primary that they pick. The Libertarians objected: they didn't want non-Libs picking their candidates and party officers.

We won in district court. The 9th Circuit upheld it as to letting non-Libs vote for party officers, but reversed and remanded as to voting for candidates. We went back in with more extensive evidence, and now win on that, too. District Court holds that the statute has a major effect on voting rights, which triggers strict scrutiny. Also that the State's interests (which were largely "this encourages more people to vote") were not within the type of "regulatory" standards that the Court allows even under a laxer scrutiny.

UPDATE: a comment blocked by the spam filter for some reason:

Congrats on the win! The "We get to vote in your primary but you can't vote in ours" never seemed fair.

What is the practical effect of the ruling? I presume at the very least, only registered ALP members will get to vote in the ALP primary. Does it also apply to the Republi-'Crat primaries as well?

Answer: it only applies directly, in AZ, and the the ALP. The Repubs and Demos were comfortable with independents, etc. voting in their primaries since (1) they have a big enough registration base to where such votes probably won't change the results and (2) since their object is to win rather than have any ideological theme (I may be dating myself, but I can remember when Ted Kennedy and wild segregationists still considered themselves the same party), they welcome anything that has the chance of drawing more votes.

Congratulations. Now if only there were such a ruling in First Circuit. In Massachusetts a large plurality of voters are not enrolled in any party, and are free to walk into the polls and take a primary ballot for any party they choose. In a close primary race it's not at all uncommon for a party's candidate to be determined by voters with absolutely no connection to the party.